I have been following stories like this for the past couple years about Burmese Pythons and it's pretty freaky. These things are primarily in the everglades, but they could very easily start being a nuisance through out Florida in time. Not to mention these things are aggressive. I would say that if Florida does not get a handle on this, you could see these things in Orlando whithin 10 years.
http://www.google.com/hostednews/ap/article/ALeqM5g557Bdx0gCIw9DZ0PuWBdpTnwqYQD99GE6HO0